In the 1960s, Jim Henson made a bunch of short films, often collaborating with composer/inventor Raymond Scott, who provided sound. Here are some of the Henson/Scott collaborations, for your viewing pleasure.
Here's a film commissioned by IBM in 1967 to sing the praises of its then-new MT/ST word processor. Note Henson's signature choppy editing style and psychedelic/surreal feel.
I very much love that IBM paid for this (they've commissioned other great films too). This is bananas, in the best possible way.
This is a real commercial for headache pills. Man, the 60s were rad around the edges. Note that Henson is narrating, though the man onscreen is an actor.
"Wheels That Go"
Short and sweet (not to mention a bit weird).
"Limbo, the Organized Mind"
The first version of this aired in 1966, and was performed again on Carson's show in 1974. Trippy, eh? Stick around until the end to see a surprise.
Jon Stone from Sesame Street throws pebbles into a pond in this experimental film created for a contest at Montreal's Expo 67.
(Via a wonderful Metafilter post, which contains more context and commentary.)